Conventional strollers are simple transportation apparatus to enable parents to move infants or babies. When arriving at the destination of an outdoor trip, the infant must be moved from the car seat to the stroller to make carrying of the infant easier. According to present regulations, an infant must be seated in a safety car seat when riding in a car. For safety considerations, the safety car seat must be fastened by a five-point safety belt. When the infant is put in a stroller, a three-point or five-point safety belt must be fastened. Hence to move a sleeping infant in the car, the five-point safety belt in the car must be unfastened, and the safety belt of the stroller is then fastened. This changeover usually wakes the infant.
To remedy the problem mentioned above, strollers in combination with a safety seats have been developed, such as the one disclosed in U.S. Pat. No. 5,676,386. It mainly includes an armrest and a safety seat assembly that may be coupled together or separated from each other so that the sleeping baby may be moved from a car to a stroller without being disturbed. The safety car seat has a matching securing mechanism to achieve anchoring. While the design for such products has heavily focused on convenience and easy operation, with products for infants safety is an important issue that often outweighs convenience. In terms of structure, the features for convenience do not necessary all meet the safety requirements. The patent mentioned above employs an elastic element to achieve automatic positioning. The securing mechanism is quite complicated. In most conventional structures, in order to improve convenience, automatic coupling is adopted, so the fastening condition of the safety seat could be inadvertently overlooked by some parents. Moreover, the growing complexity of the structures also increases the frequency of malfunction. In addition, the technical components mostly adopt elastic elements. These elements have fatigue problems and are prone to result in ineffective or failed coupling. Hence while contemporary products that use elastic elements and a single operational structure might be convenient, their complicated constructions often compromise safety.